Spanish authorities say they have arrested three members of the international group of computer hackers who call themselves Anonymous.

All three are Spanish, and between the ages of 30 and 32, said Manuel Vazquez, chief of the police department's high-tech crime unit. They were were arrested in the coastal city of Barcelona, in the region of Valencia and in the southern city of Almeria. Their names were not immediately made public.

Reuters reported that the three were involved in April's crippling attack on Sony's PlayStation network. But Sony had no immediate comment, and the information could not be confirmed by ABC News.

Vazquez said a computer server in one of the suspects' homes was used to take part in cyberattacks on targets, including two major Spanish banks, the Italian energy company Enel and the governments of Egypt, Algeria, Libya, Iran, Chile, Colombia and New Zealand.

But the men arrested today are only a small part of a loosely organized network. Messages from Anonymous have claimed the group hacked Sony, PBS, banks, credit card databases and government websites, including Egypt's and New Zealand's.

They also are believed to have posted statements on YouTube, including one this week that it said was addressed to NATO.

"Anonymous would like to remind you that the government and the people are, contrary to the supposed foundations of 'democracy,' distinct entities with often conflicting goals and desires," said a computer-generated voice that read the message. "It is Anonymous' position that when there is a conflict of interest between the government and the people, it is the people's will which must take priority."

"We do not wish to threaten anybody's way of life," it went on. "We do not wish to dictate anything to anybody. We do not wish to terrorize any nation. We merely wish to remove power from vested interests and return it to the people, who, in a democracy, it should never have been taken from in the first place."

It's been a bad year for computer security. Citibank acknowledged this week that a data security breach in early May exposed information on about 210,000 of its bankcard customers. Lockheed Martin was also the target of an attack on its internal computer network.

Adam Levin, co-founder of Credit.com and former director of the New Jersey Division of Consumer Affairs, said it is best for consumers to carry the mind-set that there will be more data breaches in the future.

"The level of sophistication of hacking has grown exponentially," Levin said. "And the bad guys are ahead of the good guys."

ABC News' Susanna Kim and The Associated Press contributed to this story.